Subterranean treatment fluids, friction reducing copolymers, and associated methods

Abstract

Aqueous treatment fluids that comprise water, and a friction reducing copolymer that comprises acrylamide in an amount in the range of from about 60% to about 90% by weight and acrylic acid in an amount in the range of from about 10% to about 20% by weight. Methods of treating portions of subterranean formation using the aqueous treatment fluid that comprise providing an aqueous treatment fluid comprising water, and a friction reducing copolymer that comprises acrylamide in an amount in the range of from about 60% to about 90% by weight and acrylic acid in an amount in the range of from about 10% to about 20% by weight; and introducing the aqueous treatment fluid into the portion of the subterranean formation.

1. A method of treating a portion of a subterranean formation, comprising:
 providing an aqueous treatment fluid comprising water, and a friction reducing copolymer consisting essentially of acrylamide in an amount in the range of from about 80% to about 90% by weight and acrylic acid in an amount in the range of from about 10% to about 20% by weight; and 
 introducing the aqueous treatment fluid into the portion of the subterranean formation. 
 
     
     
       2. The method of  claim 1  wherein the friction reducing copolymer is present in an amount in the range of from about 0.01% to about 4% by weight of the aqueous treatment fluid. 
     
     
       3. The method of  claim 1  wherein the friction reducing copolymer has a molecular weight in the range of from about 7,500,000 to about 20,000,000. 
     
     
       4. The method of  claim 1  wherein the acrylic acid is present in the friction reducing copolymer in an amount in the range of from about 12% to about 17% by weight of the friction reducing copolymer. 
     
     
       5. The method of  claim 1  wherein the aqueous treatment fluid is introduced into the portion of the subterranean formation at a rate and pressure sufficient to create or enhance one or more fractures in the portion of the subterranean formation. 
     
     
       6. The method of  claim 1  further comprising the step of preparing the aqueous treatment fluid, wherein the step of preparing the aqueous treatment fluid comprises:
 providing the friction reducing copolymer; and 
 combining the friction reducing copolymer and the water to form the aqueous treatment fluid. 
 
     
     
       7. The method of  claim 6  wherein the friction reducing copolymer is provided in a solid form, suspended in an oil-external copolymer emulsion, or as a component of an aqueous solution. 
     
     
       8. The method of  claim 6  wherein the step of providing the friction reducing copolymer comprises providing an oil-external copolymer emulsion that comprises additional water, a water-immiscible liquid, an emulsifier, and the friction reducing copolymer. 
     
     
       9. The method of  claim 8  wherein the oil-external copolymer emulsion inverts subsequent to combination with the water, releasing the friction reducing copolymer into the water with which the oil-external copolymer emulsion was combined. 
     
     
       10. The method of  claim 8  wherein the oil-external copolymer emulsion further comprises at least one of the following: an inhibitor, a salt, or an inverter. 
     
     
       11. The method of  claim 8 :
 wherein the oil external copolymer emulsion further comprises ammonium salt, 4-methoxyphenol, and an ethoxylated C12–C16 alcohol; and 
 wherein the water-miscible liquid comprises a mixture of paraffinnic hydrocarbons and napthenic hydrocarbons; and 
 wherein the emulsifier comprises a tall oil fatty acid diethanol amine, a polyoxyethylene (5) sorbitan monooleate, and a sorbitan monooleate; and 
 wherein the acrylamide is present in the friction reducing copolymer in an amount in the range of from about 80% to about 90% by weight of the copolymer. 
 
     
     
       12. The method of  claim 1  wherein the friction reducing copolymer is present in the aqueous treatment fluid in an amount in the range of from about 0.025% to about 0.1% by weight of the aqueous treatment fluid. 
     
     
       13. A method of treating a portion of a subterranean formation, comprising:
 providing an oil-external copolymer emulsion that comprises water, a water-immiscible liquid, an emulsifier, and a friction reducing copolymer that comprises acrylamide in an amount in the range of from about 60% to about 90% by weight and acrylic acid in an amount in the range of from about 10% to about 20% by weight; 
 combining the oil-external copolymer emulsion with additional water to form an aqueous treatment fluid; 
 allowing the oil-external copolymer emulsion to invert so as to release the friction reducing copolymer into the aqueous treatment fluid, after the step of combining the oil-external copolymer emulsion with the additional water; and 
 introducing the aqueous treatment fluid into the portion of the subterranean formation. 
 
     
     
       14. The method of  claim 13  wherein the friction reducing copolymer is present in the aqueous treatment fluid an amount in the range of from about 0.025% to about 0.1% by weight of the aqueous treatment fluid. 
     
     
       15. The method of  claim 13  wherein the friction reducing copolymer has a molecular weight in the range of from about 7,500,000 to about 20,000,000. 
     
     
       16. The method of  claim 13  wherein the acrylamide is present in the friction reducing copolymer in an amount in the range of from about 80% to about 90%. 
     
     
       17. The method of  claim 13  wherein the acrylic acid is present in the friction reducing copolymer in an amount in the range of from about 12% to about 17% by weight of the friction reducing copolymer. 
     
     
       18. The method of  claim 13  wherein the friction reducing copolymer further comprises at least one of the following: 2-acrylamido-2-methylpropane sulfonic acid; N,N-dimethylacrylamide; vinyl sulfonic acid; N-vinyl acetamide; or N-vinyl formamide. 
     
     
       19. The method of  claim 13 :
 wherein the oil external copolymer emulsion further comprises ammonium salt, 4-methoxyphenol, and an ethoxylated C12–C16 alcohol; and 
 wherein the water-miscible liquid comprises a mixture of paraffinnic hydrocarbons and napthenic hydrocarbons; and 
 wherein the emulsifier comprises a tall oil fatty acid diethanol amine, a polyoxyethylene (5) sorbitan monooleate, and a sorbitan monooleate; and 
 wherein the acrylamide is present in the friction reducing copolymer in an amount in the range of from about 80% to about 90% by weight of the copolymer. 
 
     
     
       20. The method of  claim 13  wherein the aqueous treatment fluid is introduced into the portion of the subterranean formation at a rate and pressure sufficient to create or enhance one or more fractures in the portion of the subterranean formation.